Pull chain socket



Dec. l2, 1944. A. G. MUELLER PULL CHAIN SOCKET Filed Feb. 24, 1943 ITM/erwten@ AclohC GLP/lue! le In" f' His Attcrmey.

Patented Dec. l2, 1944 UNITED STATES PATENT oFFlcE 2,364,995 PULL CHAIN SOCKET Adolf G. Mueller, Fairlield, Conn., assigner to General Electric Company, a corporation oi' New York Application February 24, 1943, Serial No.

Claims. relates to pull chain For a consideration of what I believe to be novel and my invention, attention is directed to the following description and the claims appended thereto in connection with the accomalong lines 2 2, 3 3 and Fig.l; Fig. 5 is a perspective, essential parts 6l is another perspective view socket.

'I'he socket comprises an outer sheet metal shell Ill with a detachable cap Il having a hub shell contact and the other 1s in the form of a central spring contact v-I'l. The screw shell contact I6 is secured to ,the the base by two SCIeWS insulating base i4. electrically connected by means of a terminal 22 and a screw 23 (Fig. 4) to the screw shell I6. The -other binding screw 20 is inclined cam surfaces 28a formed on the bottom o1' the switch chamber II. Another such engages an inclined cam 476.921 (Cl. 20o-65) are cooperatively associated with a tallic switch member movable, mehas a central 5 tionary contacts 28, 2l.

The switch mechanism includes means for effecting step-by-step rotation ciated with an insulating arc snuiling cup or is viewed from the top in Fig.

member are cooperatively cumferentially spaced cams $8 snuiling cup Il. The latter has a central bore 31 on the post 30.

'ment the snuiiing cup connected at one end to the ting cup and at its other end to the opening 45 of the base I4. .The bell mouth guide 43 is then inserted into thechain and the last ball of the chain is placed into the opening 43 of the arm 4| and the bell mouth cap assembled on the base. Finally the compression spring 38 is inserted on the upper end of the stud 30 and biased downward by attachment of the cover plate '39 to the The base with the switch mechanism and contacts thereon may then'be assembled with the outer shell and insulating lining.

Assuming that the switch is in off position, a pull onthe chain 41 causes counterclockwise turning movement of the snuftlng cup 35 when viewed in Fig. 2 until the arm 4| engages the stop 43. During such turning movement the ratchet connection between the snufiing cup 35 and the movable switch member 3| causes rotation ofthe la'tter by approximately 90 angular degrees whereby the feet 33 of the movable switch member are moved from the insulating inclined cam surfaces into engagement with the contacts 23, 21, thus closing the switch and establishing a circuit for a lamp connected to the lamp contacts. During the turning move- 35 is moved axially upward on the stud 30 against the compression of the spring. 33 until at the end of such movement the feet 33 drop downward into engagement with the contacts 26, 21, permitting quick downward movement of the snufflng cup 35 by action of the spring 33. As the pull chain 41 is released the snufilng cup 35 is forced back into its normal position in which the arm 4| engages the stop 42. The return movement of the cup 35 does not effect movement of the movable switch member 3| because the cams 36form a positive driving connection with the movable switch member only upon counterclookwise movement of the snuillng cup 35. Upon closing of the contacts 23, 21 by the movable switch member 3| the switch may be opened by another pull on the chain 41. During opening of the switch the snufling cup 35 is again reciprocated on the stud 30. The movable switch member 3| is substantially enclosed by the cup 35 so that upon opening of the switch and simultaneous downward movement of the snufiing cup 35 by action of the spring 38 the arc that may be formed between the stationary and movable contacts is eiectively extinguished. The provision of separate springsl 44, 38, one for retrieving the snuiiing cup 35 and the other for biasing the snumng cup axially on the stud 30, has the advantage of eliminating the necessity of adjusting the springs subsequent to the assembly of the switch. The springs may be chosen initially so that no subsequent adjustment thereof is necessary.

What I claim asvnew and desire to secure by Letters Patent of the United States, is:

1. Pull chain socket comprising an insulating base forming a switch chamber with a centrally disposed stud therein and a plurality owcircumferentially spaced inclined cam surfaces around the stud, a pair of stationary contacts secured to diametrically opposite cam surfaces, a rotatable switch member on the stud having a pair of diametrically opposite feet for engaging in one position said contacts and in another position a pair of insulating cam surfaces, and means for actuating the rotatable switch member including a snufling cup rotatably mounted on the stud and having cam surfaces forming a ratchet arm 4| of the snufconnection with the rotatable switch member, the cup forming a chamber to enclose the movable contacts to reduce the formation of arcs during operation.

2. Pull chain socket comprising an insulating base forming a switch chamber with a centrally disposed stud therein and a plurality of circumferentially spaced inclined cam surfaces around the stud, a pair of stationary contacts secured to diametrically opposite able switch member on the stud having a pair of diametrically opposite feet for engaging in one position said contacts and in another position a pair of insulating camsurfaces, and means` for `actuating the rotatable switch member and' for substantially enclosing the cooperating contacts including a snuffing cup rotatably mounted on the stud and having cam surfaces forming a ratchet connection with the rotatable switch member, means limitingv rotary movement of the snumng cup, a spring normally biasing the cup into a fixed angular position and another spring for biasing the cup axially towards the rotatable switch member.

3. Pull chain socket comprising a base forming a switch chamber with a central stud and circumferentially spaced inclined insulating cam surfaces around the stud, stationary contact means secured to alternate cam surfaces, a rotatable switch member mounted on the stud for electrically connecting the stationary contacts, and means for rotating the rotatable switch member comprising a snumng cup rotatably mounted on the stud and having cams forming a ratchet connection with the rotatable switch member, said cup forming a chamber enclosing substantially the rotatable switch member and portions of the stationary contact means to effect quick extinguishing of arcs between the rotatable switch member and the stationary contacts upon opening of the switch.

4. An electric switch for pull chain sockets comprising a base having a central stud, a plurality of circumferentially spaced cam surfaces around the stud, stationary contact means mountedon alternate cam surfaces, a rotatable switch member mounted on the stud for electrically connecting the stationary contacts, means for rotating the rotatable switch member comprising ratchet teeth formed on the rotatable switch member, and a snuiiing cup rotatablymounted on the stud forming a chamber substantially enclosing the rotatable switch member and portions of the stationary contact means, said cup having cams forming a ratchet connection with the ratchet teeth.

5. An electric switch for pull chain sockets comprising a, base having a central stud, a plurality of circumferentially spaced cam surfaces around the stud, stationary contact means mounted on alternate cam surfaces, a rotatable switch member mounted on the stud having feet for electrically connecting the stationary contacts, means for rotating the rotatable switch member comprising ratchet teeth formed on the rotatable switch member, a snufilng cup rotatably mounted on the stud substantially forming a chamber for enclosing the rotatable switch member and having cams forming a ratchet connection with the ratchet teeth, stops on the base limiting angular movement of the snuiiing cup, and separate springs for biasing the snufng cup towards one of the stops and towards the rotatable switch member respectively.

- ADOLF G. MUEILER.

cam surfaces, a rotat- 

